A square pole, also known as a square perch, is an obsolete unit of land area measurement that was historically used in some English-speaking countries, including the United States and the United Kingdom. It is part of the older system of land measurement.
One square pole is equivalent to one square perch. In terms of modern measurements, one square pole is approximately equal to 25.29285264 square meters (m²) or 0.00625 acres.
As with other outdated units of land area measurement, the square pole is no longer commonly used in modern land transactions or legal documents. More standardized systems of measurement, such as square meters and square feet, have largely replaced these units.
The electron cross-section, often referred to as the electron scattering cross-section or simply the electron cross-section, is a term used in the fields of nuclear and particle physics to describe the likelihood of electrons interacting with other particles, such as atomic nuclei or other electrons, when they are subjected to various types of scattering experiments or interactions.
The electron cross-section is typically expressed in units of area, such as square meters (m²) or square femtometers (fm²), and it represents the effective target area presented by an electron for a particular type of interaction or scattering process. It is used to quantify the probability of electron interactions occurring in various experimental setups.